A new isotropic and decoupled 6-DoF parallel manipulator

The paper discusses the concepts of isotropy and decoupling in n-DoF (degrees of freedom) manipulators: isotropy means that its kinetostatic properties are identical in all directions, while decoupling means that each DoF of the end effector is controlled by a single actuator. The role of different Jacobian matrices in the isotropy, decoupling and in the general mobility analysis of the manipulators is revised. These concepts are applied to a Gough-Stewart platform showing that it may be isotropic, but not decoupled. A modification of its leg structure is suggested to develop some new 6-DoF PKMs (parallel kinematic machine) decoupled and isotropic in the considered configuration. An introduction to the mobility analysis of serial and parallel manipulators is also presented. (C) 2012 Elsevier Ltd. All rights reserved.